package com.ut.autobot;
import java.security.MessageDigest;

public class MD5 
{ 
  /* 
   * A Java implementation of the RSA Data Security, Inc. MD5 Message 
   * Digest Algorithm, as defined in RFC 1321. 
   * Based on the JavaScript implementation of Paul Johnston 
   *      Copyright (C) Paul Johnston 1999 - 2000. 
   *      See http://pajhome.org.uk/site/legal.html for details. 
   * Java Version by Thomas Weber (Orange Interactive GmbH) 
   */ 
   
  /* 
   * Convert a 32-bit number to a hex string with ls-byte first 
   */ 
  String hex_chr = "0123456789abcdef"; 
  
  int[] r1Shifts 	= { 7, 12, 17, 22,  7, 12, 17, 22,  7, 12, 17, 22,  7, 12, 17, 22 };
  int[] r2Shifts 	= {5, 	9, 14, 20,  5,  9, 14, 20,  5,  9, 14, 20,  5,  9, 14, 20 };
  int[] r3Shifts 	= { 4, 11, 16, 23,  4, 11, 16, 23,  4, 11, 16, 23,  4, 11, 16, 23 };
  int[] r4Shifts	= { 6, 10, 15, 21,  6, 10, 15, 21,  6, 10, 15, 21,  6, 10, 15, 21 }; 

  
  private String rhex(int num) 
  { 
    String str = ""; 
    for(int j = 0; j <= 3; j++) 
      str = str + hex_chr.charAt((num >> (j * 8 + 4)) & 0x0F) + hex_chr.charAt((num >> (j * 8)) & 0x0F); 
    return str; 
  } 
   
  /* 
   * Convert a string to a sequence of 16-word blocks, stored as an array. 
   * Append padding bits and the length, as described in the MD5 standard. 
   */ 
  private int[] str2blks_MD5(String str) 
  { 
    int nblk = ((str.length() + 8) >> 6) + 1; 
    int[] blks = new int[nblk * 16]; 
    int i = 0; 
    for(i = 0; i < nblk * 16; i++) { 
      blks[i] = 0; 
    } 
    for(i = 0; i < str.length(); i++) { 
      blks[i >> 2] |= str.charAt(i) << ((i % 4) * 8); 
    } 
    blks[i >> 2] |= 0x80 << ((i % 4) * 8); 
    blks[nblk * 16 - 2] = str.length()*8; 
       
    return blks; 
  } 
   
  /* 
   * Add integers, wrapping at 2^32 
   */ 
  private int add(int x, int y) 
  { 
	int lsw = (x & 0xFFFF) + (y & 0xFFFF);
	int msw = (x >> 16) + (y >> 16) + (lsw >> 16);
	return (msw << 16) | (lsw & 0xFFFF);
  } 
   
  /* 
   * Bitwise rotate a 32-bit number to the left 
   */ 
  private int rol(int num, int cnt) 
  { 
    return (num << cnt) | (num >>> (32 - cnt)); 
  } 
   
  /* 
   * These functions implement the basic operation for each round of the 
   * algorithm. 
   */ 
  private int cmn(int q, int a, int b, int x, int s, int t) 
  { 
    return add(rol(add(add(a, q), add(x, t)), s), b); 
  } 
  private int ff(int a, int b, int c, int d, int x, int s, int t) 
  { 
    return cmn((b & c) | ((~b) & d), a, b, x, s, t); 
  } 
  private int gg(int a, int b, int c, int d, int x, int s, int t) 
  { 
    return cmn((b & d) | (c & (~d)), a, b, x, s, t); 
  } 
  private int hh(int a, int b, int c, int d, int x, int s, int t) 
  { 
    return cmn(b ^ c ^ d, a, b, x, s, t); 
  } 
  private int ii(int a, int b, int c, int d, int x, int s, int t) 
  { 
    return cmn(c ^ (b | (~d)), a, b, x, s, t); 
  } 
   
  /* 
   * Take a string and return the hex representation of its MD5. 
   */ 
  
  
  public String calcMD5(String str) 
  { 
    int[] x = str2blks_MD5(str); 
    int a = 1732584193; 
    int b = -271733879; 
    int c = -1732584194; 
    int d = 271733878; 
   
    for(int i = 0; i < x.length; i += 16) 
    { 
    	
      int olda = a; 
      int oldb = b; 
      int oldc = c; 
      int oldd = d; 
      
      a = ff(a, b, c, d, x[i+ 0], 7 , -680876936); 
      d = ff(d, a, b, c, x[i+ 1], 12, -389564586); 
      c = ff(c, d, a, b, x[i+ 2], 17, 606105819); 
      b = ff(b, c, d, a, x[i+ 3], 22, -1044525330); 
      a = ff(a, b, c, d, x[i+ 4], 7 ,-176418897); 
      d = ff(d, a, b, c, x[i+ 5], 12, 1200080426); 
      c = ff(c, d, a, b, x[i+ 6], 17, -1473231341); 
      b = ff(b, c, d, a, x[i+ 7], 22, -45705983); 
      a = ff(a, b, c, d, x[i+ 8], 7 , 1770035416); 
      d = ff(d, a, b, c, x[i+ 9], 12, -1958414417); 
      c = ff(c, d, a, b, x[i+10], 17, -42063); 
      b = ff(b, c, d, a, x[i+11], 22, -1990404162); 
      a = ff(a, b, c, d, x[i+12], 7 , 1804603682); 
      d = ff(d, a, b, c, x[i+13], 12, -40341101); 
      c = ff(c, d, a, b, x[i+14], 17, -1502002290); 
      b = ff(b, c, d, a, x[i+15], 22, 1236535329); 
      
      a = gg(a, b, c, d, x[i+ 1], 5 , -165796510); 
      d = gg(d, a, b, c, x[i+ 6], 9 , -1069501632); 
      c = gg(c, d, a, b, x[i+11], 14, 643717713); 
      b = gg(b, c, d, a, x[i+ 0], 20, -373897302); 
      a = gg(a, b, c, d, x[i+ 5], 5 , -701558691); 
      d = gg(d, a, b, c, x[i+10], 9 , 38016083); 
      c = gg(c, d, a, b, x[i+15], 14, -660478335); 
      b = gg(b, c, d, a, x[i+ 4], 20, -405537848); 
      a = gg(a, b, c, d, x[i+ 9], 5 , 568446438); 
      d = gg(d, a, b, c, x[i+14], 9 , -1019803690); 
      c = gg(c, d, a, b, x[i+ 3], 14, -187363961); 
      b = gg(b, c, d, a, x[i+ 8], 20, 1163531501); 
      a = gg(a, b, c, d, x[i+13], 5 , -1444681467); 
      d = gg(d, a, b, c, x[i+ 2], 9 , -51403784); 
      c = gg(c, d, a, b, x[i+ 7], 14, 1735328473); 
      b = gg(b, c, d, a, x[i+12], 20, -1926607734); 
      
      a = hh(a, b, c, d, x[i+ 5], 4 , -378558); 
      d = hh(d, a, b, c, x[i+ 8], 11, -2022574463); 
      c = hh(c, d, a, b, x[i+11], 14, 1839030562); 
      b = hh(b, c, d, a, x[i+14], 23, -35309556); 
      a = hh(a, b, c, d, x[i+ 1], 4 , -1530992060); 
      d = hh(d, a, b, c, x[i+ 4], 11, 1272893353); 
      c = hh(c, d, a, b, x[i+ 7], 16, -155497632); 
      b = hh(b, c, d, a, x[i+10], 23, -1094730640); 
      a = hh(a, b, c, d, x[i+13], 4 , 681279174); 
      d = hh(d, a, b, c, x[i+ 0], 11, -358537222); 
      c = hh(c, d, a, b, x[i+ 3], 16, -722521979); 
      b = hh(b, c, d, a, x[i+ 6], 23, 76029189); 
      a = hh(a, b, c, d, x[i+ 9], 4 , -640364487); 
      d = hh(d, a, b, c, x[i+12], 11, -421815835); 
      c = hh(c, d, a, b, x[i+15], 16, 530742520); 
      b = hh(b, c, d, a, x[i+ 2], 23, -995338651); 
      
      a = ii(a, b, c, d, x[i+ 0], 6 , -198630844); 
      d = ii(d, a, b, c, x[i+ 7], 10, 1126891415); 
      c = ii(c, d, a, b, x[i+14], 15, -1416354905); 
      b = ii(b, c, d, a, x[i+ 5], 21, -57434055); 
      a = ii(a, b, c, d, x[i+12], 6 , 1700485571); 
      d = ii(d, a, b, c, x[i+ 3], 10, -1894986606); 
      c = ii(c, d, a, b, x[i+10], 15, -1051523); 
      b = ii(b, c, d, a, x[i+ 1], 21, -2054922799); 
      a = ii(a, b, c, d, x[i+ 8], 6 , 1873313359); 
      d = ii(d, a, b, c, x[i+15], 10, -30611744); 
      c = ii(c, d, a, b, x[i+ 6], 15, -1560198380); 
      b = ii(b, c, d, a, x[i+13], 21, 1309151649); 
      a = ii(a, b, c, d, x[i+ 4], 6 , -145523070); 
      d = ii(d, a, b, c, x[i+11], 10, -1120210379); 
      c = ii(c, d, a, b, x[i+ 2], 15, 718787259); 
      b = ii(b, c, d, a, x[i+ 9], 21, -343485551); 
      b = ii(b, c, d, a, x[i+ 9], 21, -343485551); 
      
      a = add(a, olda); 
      b = add(b, oldb); 
      c = add(c, oldc); 
      d = add(d, oldd); 
      
      
    } 
    return rhex(a) + rhex(b) + rhex(c) + rhex(d); 
  } 

}